Magnetic damper for electric arcs



W. E. HARRISON MAGNETIC DAMPER FOR ELECTRIC ARCS Filed Nov. 20. 1920 mmamZ/m/m BY A'TTORNEY WITNESSES:

Patented Oct. 14, 1924.

UNITED STATES 1,511,332 PATENT OFFICE.

WILLIAM E. HARRISON, F PHILADELPHIA, PENNSYLVANIA, I

& MANUFACTURING COMPANY, A CORPORATION OF PENN- INGHOUSE ELECTRIC SYLVAN IA.

ASSIGNOB '.120 WEST- MAGNETIC DAMPER FOB ELECTRIC ARCS.

Application filed November 20, 1920. Serial No. 425,517.

To all whom it may concern:

Be it known that I, WILLIAM E. HARRI- son, a citizen of the United States, and a resident of Philadelphia, in the county of Philadelphia and State of Pennsylvania,- have invented a new and useful Improvement in Magnetic Dampers for Electric Arcs, of which the following is a specification.

My invention relates to circuit interrupters and particularly to means for controlling the arcs thereof.

One object of my invention is to provide means for preventing the deflection of arcs to adjacent objects.

Another object of my invention is to provide means for so affecting an are as to permit it to assume a path of movement of substantially any desired shape.

Another object of my invention is to provide means responsive to the movement of an are for inducing a magnetic flux field or fields which affect the arc.

Heretofore, it has been usual to assist in the suppre sion and extinguishment of electric arcs b means of electromagnetic flux fields induced by coils or windings. The fluxes so induced are adapted to react with an arc to disrupt it or to force it away from its oint of origin, thus lengthening the are an increasing its internal resistance until current ceases to flow and the arc is extinguished. a

In practicing my invention, I provide means forinducing an electromagnetic flux field or fields at such selectively predetermined position or positions with respect to the normal arc path as to control or govern the path to be assumed by an arc. This means may take the form of flux-forming members that are energized by a separate circuit or: from the circuit of the are or it may, referably, comprise conducting members t at react with the arc to have fluxes for affecting the are induced in them.

Fi ure 1 of the accompanying drawings is a ront elevational view of a portion of a circuit interrupter embodying m invention, looking into the arc chute and t rough certain flux-forming loop members in which fluxes are induced by the arc.

Fig. 2 is a side elevational view of the device shown in Fig. 1.

Figs. 3 and 4 are. views similar to Figs. 1

and 2 showing a different arrangement of the flux-forming loop members and Fig. 5 is a diagrammatic view, similar to Fig. 1, showing a wound flux loop that is positively excited from the circuit of the arc.

As shown in Figs. 1 and 2, stationary and movablecontact members 1 and 2, respectively, that may be supported and actuated in an usual or suitable manner (not showni are disposed between the side plates 3 of the usual arc chute. A blowout coil 4 disposed between the plates 3 at the rear 0 the chute, co-operates, in a usual and wellknown manner, with pole members or plates 5 to impel an incipient are from the contact members, when the interrupter is o ened.

My invention consists in the placing of magnetic-flux-forming members 6 and 7 that, in Figs. 1, 2, 3 and 4, are closed conducting loops, preferably of copper, in any advantageous position to divert or direct the are as desired.

.In accordance with the well-known principle that induced fluxes always oppose the action of the fluxes which set narrow loops 6, disposed diagonally across the inner sides of the plates 3, will tend to prevent the are from passing 'therethrough and limit the arc to a relatively narrow path 8 between the loops 6.

Inasmuch as arcs sometimes tend to flash them up, the

backwardly from the exit of the chute tosurfaces of the plates 3, and loops 10 are disposed vertically above the arc chute to pre- -vent arcs or portions thereof from bein deflected in the general direction indicate by arrows 11. The loo s 9 and 10 are similar in construction to t e loops 6 and 7. In fact, conducting members similar to the members 6, 7, 9 and 10 of the above described forms of my invention may be variously arranged to deflect and to govern the arcs in any desired manner and to cause it to assume any desired shape. A brace 11 of asbestos lumber is riveted'to the loops 10 for holding them in place.

As shown in Fig. 5, loop members 12, only one of which is shown, may be arranged similar to the loop members 7 of Figs. 1 and' 2 and consist of wound coils connected in circuit with the blowout 'coil 5 and the contact members 1 and 2; In this form of my invention, the arc-controlling fluxes are caused by the positive passing of externally-applied current therethrough and not an arc thereon comprising a conducting member of loop shape capable of generating an electromagnetic flux field for afiecting the arcand responsive to movements of I said are relatively thereto.

2. In a circuit lnterrupter, the combination with relatively movable contact members, of means for controlling the shape of an arc thereon comprising a plurality of conducting members of loop shape disposed in selective predetermined positions adjacent :to the contact members and capable of gencrating electromagnetic flux fields for aftesting the arc.

3. In a circuit interrupter, thecombinadescribed partion with relatively movable contact members, of means for controlling the shape of an arc thereon comprising a conducting member of loop shape in which there is induced an electromagnetic flux field through whichpassage of the arc is opposed upon relative movement of the are.

4. In a circuit interrupter, the combination with relatively movable contact members, of means for screening an are against certain normally directed movements comprising a plurality of conducting loop members capable of generating a magnetic flux to oppose movement of the are through the loops, e

5. The combination with electrical terminal members, of a conductor disposed adjacent thereto and responsive to relative movement of an arc with respect thereto to generatea magnetic-flux field for affecting the arc.

6. In a circuit interrupter, the combina tion with relatively movable contact members, of a conductor of closed-loop shape disposed adjacent thereto and responsive to relative movement of an arc with respect thereto to generate a magnetic-flux field for effecting the arc. i

7, In a circuit interrupter, the combination'with relatively movable contact members and an arc chute therefor, of a plurality or conductors of closed-loop shape mounted on said chute, said conductors being capable of generating magnetic-flux fields in response to movement of an arc to direct the letter.

In testimony whereof, I have hereunto subscribed my name this 4 day of November, 1920;

WILLIAM E. HARRISON. 

